71, Similar Figures and Proportions

1
7-1, Similar Figures and Proportions

• Objectives
• Identify similar figures
• Determine the ratio of similarity for similar
  figures
• Use the ratio of similarity to form proportions
• Find the value of an unknown using the product of
  the means and the product of the extremes

2
Terms

• Similar having the same size and shape
• Ratio comparison of two like quantities
• a or ab
• b
• Proportion the equality of two ratios
• a c
• b d

3
Ratio of Similarity

• A ratio comparing the relative sizes of similar
  figures

2
6
2
Side
Diameter
4
The ratio of similarity of these squares is
___________
The ratio of similarity of these circles is
___________
2 6 or 2 1 6 3
4 2 or 4 2 2 1
4
In any proportion, the product of the extremes
equals the product of the means

• Given any proportion,
• To Prove ad bc

means
extremes
5
7-1, Similar Figures and Proportions
Date _____________________________

• Objectives
• Identify similar figures
• Determine the ratio of similarity for similar
  figures
• Use the ratio of similarity to form proportions
• Find the value of an unknown using the product of
  the means and the product of the extremes

6
Terms

• Similar having the ____ size and shape
• Ratio ______________ of two _____
  _______________
• Proportion the _______________ of two
  _____________

7
Ratio of Similarity

• A ratio comparing the relative sizes of similar
  figures

The ratio of similarity of these squares is
___________
The ratio of similarity of these circles is
___________
8
In any proportion, the product of the extremes
equals the product of the means

• Given any proportion,
• To Prove ad bc